1. Field of the Invention
This invention relates to an outboard motor steering system, and more specifically to a system for introducing a lubricant into a steering cable for a pivotable outboard motor.
2. Background of the Invention
The original purpose of an outboard motor was to provide a small portable motor for a rowboat. As the outboard motor evolved, significant improvements were implemented in the output horsepower of the outboard motor. As a consequence of the increase in the output horsepower of the outboard motor the size and weight of the outboard motor increased dramatically. The early outboard motors, as well as many of the present day low horsepower outboard motors, were steered by a manually operated steering tiller. An operator of the outboard motor was position in the stern of the vessel, as is well known to those skilled in the art.
As outboard powered vessels increased in the available horsepower and size, remote engine controls and steering were developed enabling the operator to be positioned forward in the vessel to provide a more unobstructed view for the operator. In addition, the weight distribution in the vessel was improved when the operator was positioned forward in the vessel.
Early steering systems comprised a steering wheel for rotating a cable drum. A flexible steering cable was wrapped about the cable drum near the center of the cable and both ends of the cable were attached to the outboard motor. The cable was guided by a series of pulleys attached to the vessel. Rotating the steering wheel and the cable drum changed the position of one end of the cable relative to the other end of the cable, thereby causing the motor to pivot and to steer the vessel. This steering system was commonly referred to as a cable/pulley system.
This steering system remained virtually unimproved for many years and performed satisfactorily in service with only minor maintenance. As motor horsepower continued to increase, it became apparent that the cable/pulley system would no longer provide satisfactory results.
The next innovation in steering systems was to provide a steering wheel affixed to a helm unit which converts the rotary steering action to a linear push-pull action of a cable within a cable sheath. The sheathed cable was led from the steering station to an aft motor location where the cable sheath was directed and affixed to a cable mounting tube which was an integral part of the motor mount. The cable exited from the opposite end of the cable mounting tube from the cable sheath and was linked to the outboard motor. Rotation of the steering wheel effected an extension or a retraction of the cable relative to the cable sheath, thereby effecting a pivoting action of the outboard motor. Other variations of this system were developed for outboard motors without integral cable mounting tubes. This steering system was commonly referred to as a sheathed cable system.
The sheathed cable steering system has been a substantial improvement over the cable/pulley system since the sheathed cable system offers more positive steering with less effort and requires less maintenance than the cable/pulley system.
Unfortunately, the sheathed cable steering system suffers from a serious corrosion problem whereby the extension and retraction of the cable from the cable mounting tube permits the entry of foreign materials into the cable mounting tube. Entry of corrosive materials such as seawater produces corrosion byproducts which require an increase in steering effort to overcome the increased friction between the cable and the cable mounting tube. Ultimately, seizure of the cable within the cable mounting tube will occur unless the problem is addressed. The recommendations of the manufacturers call for the application of grease on the surface of the cable external to the cable mounting tube in an effort to introduce lubrication into the interior of the cable mounting tube. This lubrication scheme has met with little success.
Therefore, it is an object of the present invention to provide an improved system for introducing a lubricant into a cable mounting tube of a pivotable outboard motor in response to a motorboat steering device.
Another object of this invention is to provide an improved system for introducing a lubricant into a cable mounting tube of a pivotable outboard motor wherein a resilient seal ring is disposed in a recess of a nut body affixed to the cable mounting tube creates a seal between the nut body and the inner cable to prevent intrusion of foreign matter into the cable bore and cable mounting tube.
Another object of this invention is to provide an improved system for introducing a lubricant into a cable mounting tube of a pivotable outboard motor wherein a grease fitting disposed in a nut body affixed to the cable mounting tube enables the introduction of the lubricant into the cable bore and cable mounting tube.
Another object of this invention is to provide an improved system for introducing a lubricant into a cable mounting tube of a pivotable outboard motor wherein the improved system may be installed on an existing sheathed cable steering system.
Another object of this invention is to provide an improved system for introducing a lubricant into a cable mounting tube of a pivotable outboard motor wherein the improved system may be installed on an existing sheathed cable steering system without the need for specialized tools or specialized skills.
Another object of this invention is to provide an improved system for introducing a lubricant into a cable mounting tube of a pivotable outboard motor which provides a low cost solution for the introduction of the lubricant into the cable bore and cable mounting tube.
The foregoing has outlined some of the more pertinent objects of the present invention. These objects should be construed as being merely illustrative of some of the more prominent features and applications of the invention. Many other beneficial results can be obtained by applying the disclosed invention in a different manner or modifying the invention with in the scope of the invention. Accordingly other objects in a full understanding of the invention may be had by referring to the summary of the invention, the detailed description describing the preferred embodiment in addition to the scope of the invention defined by the claims taken in conjunction with the accompanying drawings.